1. Field of the Invention
The present invention relates to an image forming apparatus and image forming method using a light beam and, more particularly, to an image forming apparatus and image forming method for forming an image by a scanning optical system which uses a plurality of light beams.
2. Description of Related Art
A conventional image forming apparatus using a scanning optical system for scanning a plurality of light beams emitted by a plurality of laser sources can decrease the rotational speed (revolutions) of a polygon mirror in comparison with a scanning optical system for scanning a single laser beam, and is more advantageous in durability and vibrations.
To the contrary, an image forming apparatus using a single laser beam can almost simultaneously perform generation of an image signal and exposure by a laser beam. In the use of a plurality of laser beams, the apparatus accumulates a plurality of image signals generated every line and then executes exposure by a laser beam.
These types of the conventional image forming apparatus using a plurality of laser beams requires control of accumulating image signals generated every line. This complicates a circuit necessary to generate an image signal, and inhibits a low-cost arrangement.